title: Improving the reach of vaccines to low-resource regions, with a needle-free vaccine delivery device and long-term thermostabilization.
abstract: Dry-coated microprojections can deliver vaccine to abundant antigen-presenting cells in the skin and induce efficient immune responses and the dry-coated vaccines are expected to be thermostable at elevated temperatures. In this paper, we show that we have dramatically improved our previously reported gas-jet drying coating method and greatly increased the delivery efficiency of coating from patch to skin to from 6.5% to 32.5%, by both varying the coating parameters and removing the patch edge. Combined with our previous dose sparing report of influenza vaccine delivery in a mouse model, the results show that we now achieve equivalent protective immune responses as intramuscular injection (with the needle and syringe), but with only 1/30th of the actual dose. We also show that influenza vaccine coated microprojection patches are stable for at least 6 months at 23°C, inducing comparable immunogenicity with freshly coated patches. The dry-coated microprojection patches thus have key and unique attributes in ultimately meeting the medical need in certain low-resource regions with low vaccine affordability and difficulty in maintaining "cold-chain" for vaccine storage and transport.
authors.affiliation: The University of Queensland, Delivery of Drugs and Genes Group (D(2)G(2)), Australian Institute for Bioengineering and Nanotechnology, Brisbane.
authors.forename: Xianfeng
authors.initials: X
authors.lastname: Chen
authors.forename: Germain J P
authors.initials: GJ
authors.lastname: Fernando
authors.forename: Michael L
authors.initials: ML
authors.lastname: Crichton
authors.forename: Christopher
authors.initials: C
authors.lastname: Flaim
authors.forename: Sally R
authors.initials: SR
authors.lastname: Yukiko
authors.forename: Emily J
authors.initials: EJ
authors.lastname: Fairmaid
authors.forename: Holly J
authors.initials: HJ
authors.lastname: Corbett
authors.forename: Clare A
authors.initials: CA
authors.lastname: Primiero
authors.forename: Alexander B
authors.initials: AB
authors.lastname: Ansaldo
authors.forename: Ian H
authors.initials: IH
authors.lastname: Frazer
authors.forename: Lorena E
authors.initials: LE
authors.lastname: Brown
authors.forename: Mark A F
authors.initials: MA
authors.lastname: Kendall
mesh_terms: D000818:Animals; D000906:Antibodies / Q000097:blood / Q000276:immunology; D020405:Dermis / Q000473:pathology / Q000648:ultrastructure; D003906:Developing Countries; D016503:Drug Delivery Systems / Q000191:economics / Q000295:instrumentation* / Q000379:methods*; D004355:Drug Stability; D004817:Epidermis / Q000473:pathology / Q000648:ultrastructure; D006385:Hemagglutination Inhibition Tests; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000737:chemistry / Q000191:economics / Q000276:immunology; D008747:Methylcellulose / Q000737:chemistry; D051379:Mice; D008810:Mice, Inbred C57BL; D008855:Microscopy, Electron, Scanning; D009975:Orthomyxoviridae / Q000276:immunology; D010047:Ovalbumin / Q000008:administration & dosage; D012825:Silicon / Q000737:chemistry; D012867:Skin / Q000276:immunology / Q000473:pathology / Q000648:ultrastructure; D034421:Sus scrofa; D014611:Vaccination / Q000295:instrumentation / Q000379:methods; D014612:Vaccines / Q000008:administration & dosage* / Q000737:chemistry / Q000191:economics* / Q000276:immunology
chemical_list: D000906:Antibodies; D007252:Influenza Vaccines; D014612:Vaccines; D008747:Methylcellulose; D010047:Ovalbumin; D012825:Silicon